Red White and Bleu Slaw

I have a small catering event coming up (50 people) and they have requested a red white and bleu slaw that had at a restaurant somewhere in upstate New York. From what they told me it was vinegar based with red and white cabbage and bleu cheese. I found a recipe via google and I wasn't impressed:

Ingredients
3 tablespoons white wine vinegar
1 tablespoon sugar
1/3 cup Extra Virgin Olive Oil
Salt and freshly ground black pepper
1 cup crumbled blue cheese
2 cups red cabbage, shredded
4 cups white cabbage, shredded
1 bunch scallions, thinly sliced

I did sub apple cider vinegar for the white wine vinegar and perhaps that is why the dressing fell flat. I don't think the apple cider vinegar can stand up to the bleu cheese. Any ideas on how I can improve upon this or see any flaws in the recipe?

I would add bacon!

Don't combine the cabbages too soon or the red will turn everything red/purple. Mixing a couple hours ahead is just fine; just don't mix together the night before. Have fun!

Maybe add some bleu cheese to this:

2 C shredded red cabbage
2 C shredded white cabbage
2 C grated peeled carrots
1/2 C finely minced yellow onions
1/3 C red wine vinegar
1/4 C granulated sugar
1 TBSP prepared Dijon mustard
salt and pepper
2/3 C olive oil
1 TBSP of caraway seeds

It doesn't have to be exactly like the one they had in the restaurant, just as long as it tastes good. They trust my palate and the first batch I made didn't cut it.